An exception not mentioned in the method signature occurred
(excluding runtime exceptions). The
UnexpectedException exception object contains the
underlying exception that was thrown by the server.

java.rmi.ServerError

Any error that occurs while the server is executing a remote
method. The ServerError exception object contains the
underlying error that was thrown by the server,

java.rmi.ServerException

This exception is thrown as a result of a remote method
invocation when a RemoteException is thrown while
processing the invocation on the server, either while unmarshalling
the arguments or executing the remote method itself. For examples,
see Section A.3.1,
"Possible Causes of java.rmi.ServerException".

java.rmi.ServerRuntimeException

note: this exception is deprecated as of Java 2 SDK,
Standard Edition, v1.2

This exception is not thrown by servers running Java 2 SDK,
Standard Edition, v1.2-compatible versions. A
RuntimeException is propagated to clients intact.